October 10, 1995
12:00 AM (EDT)

News Release Number: STScI-1995-37

Hubble Discovers Bright New Spot on Io

October 10, 1995: This pair of images of Jupiter's volcanic moon Io, taken with the Hubble telescope, shows the surprising emergence of a 200-mile-wide, yellowish-white feature near the center of the moon's disk [photo on the right]. This represents a more dramatic change in 16 months than any seen over the previous 15 years, say researchers. They suggest the spot may be a new class of transient feature on the moon. For comparison the photo on the left was taken in March 1994, before the spot emerged. The photo indicates that Io's surface had undergone only subtle changes since it was last seen close-up by the Voyager 2 probe in 1979.